isx 11.9 diesel engine

The Model 460 engine brake, developed in conjunction with Cummins, was built for the Cummins ISX 11.9 diesel engine and is rated between 346 and 390 hp at 1,900-2,100 rpm. It will be offered as optional equipment, comprising two engine brake housings and special exhaust valve bridges.
JACOBS VEHICLE SYSTEMS, jakebrake.com